1. Field of the Invention
This invention relates to an improved seal for a wheel hub and axle assembly, and more specifically, to an improved rotary fluid seal for use between a heavy wheel hub and an axle spindle which serves to pilot the wheel hub onto the axle spindle during assembly.
2. Description of the Prior Art
The improved seal is particularly useful in a wheel hub and axle assembly that includes a liquid cooled, multiple disc friction brake mechanism of the type generally disclosed in application Ser. No. 307,818 filed on Oct. 2, 1981. Although prior art seals have been utilized to provide a rotary liquid seal between the wheel hub and axle spindle of such assemblies, the seal is located in an area which is not visable as the wheel hub is assembled to the axle spindle and the resilient sealing element may be rolled over or damaged during such assembly.
The wheel hub and axle assemblies to which the present invention relates are heavy duty assemblies primarily used on off-highway vehicles for construction, mining or agricultural purposes. Each wheel hub may weigh on the order of 150 to 300 pounds and may be 12 to 20 inches in diameter and 12 to 18 inches in axial length. During assembly, the wheel hubs are lifted by mechanical means until the bore is substantially aligned with the spindle and then moved, usually manually, axially along the spindle. Any misalignment between the wheel hub bore and the axle spindle will cause undesirable contact between the leading parts of the hub and axle spindle. The location of the spindle seal is such that it would be subject to such contact and the radially inward projecting metal flanges of conventional seals have been deformed by such contact. It is therefore an object of the present invention to avoid these problems.